What render engine to use with the VSE?
There is a quite important difference when you render Video footage only:

Only with Blender Internal you have the option of using Anti-Aliasing.


And there is a bit of a speed gain or loss depending on your settings there. But it makes a huge difference as soon as you activate a Scale function of at least one Strip. Cranking the samples per pixel up there didn't really affect my image quality nor speed, so you could leave it at 5, but switching it off completely results in a performance increase, but a visible image quality decrease on edges.

GPU Usage is only available in Cycles though. And depending whether you want to include rendered footage from a Scene as well and what effect  you want to achieve (basically more photorealism vs. speed) you need to select your Engine accordingly.

So in your case I'd suggest you'd use Blender Internal.